Recent Accounting Standards - Additional Information (Detail) $ in Thousands	Dec. 31, 2017 USD ($)
Retained Earnings [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reclassification of the Income Tax Effects of the Tax Cuts and Jobs Act from accumulated other comprehensive loss	$ 130
AOCI Attributable to Parent [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reclassification of the Income Tax Effects of the Tax Cuts and Jobs Act from accumulated other comprehensive loss	$ (130)

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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